Answer:
5511 J
Explanation:
Applying,
Q = Cm.................... Equation 1
Where Q = amount of heat required to convert ice, C = Heat of fusion of water, m = mass of ice
From the question,
Given: C = 334 J/g, m = 16.5 g
Substitute these values into equation 2
Q = 334(16.5)
Q = 5511 J
Hence, the amount of heat required is 5511 J
Answer: a) pH of a 0.1 M vinegar solution is 2.9
b) It is an acid as pH is less than 7
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
Acids have pH ranging from 1 to 6.9, bases have pH ranging from 7.1 to 14 and neutral solutions have pH equal to 7.
As vinegar is a weak acid, its dissociation is represented as;
cM 0 0
So dissociation constant will be:
Give c= 0.1 M
![[H^+]=c\times \alpha](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3Dc%5Ctimes%20%5Calpha)
![[H^+]=0.1\times \alpha](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D0.1%5Ctimes%20%5Calpha)
Also ![pH=-log[H^+]](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%2B%5D)
![pH=-log[1.3\times 10^{-3}]=2.9](https://tex.z-dn.net/?f=pH%3D-log%5B1.3%5Ctimes%2010%5E%7B-3%7D%5D%3D2.9)
Thus pH of a 0.1 M vinegar solution is 2.9
As pH is less than 7, it is an acid.
<span> Speicific heat of water is 4.2j/gm*C </span>
<span>Thus 4.2 Joules of energy is required to heat 1 gm water to 1*C. </span>
<span>or 4.2 x 30 Joules enery is required to heat 1x30 gm water by 1*C </span>
<span>or 4.2 x 30 x 80 Joules enery is required to heat 1 x 30 gm water by (100-20)*C( or required to be removed from water to cool it) </span>
Answer: 0.4
Explanation: The easiest way to do this is to get a denominator of 10. To do this, multiply each number in 2/5 by 2. You will get the fraction 4/10. With the denominator of 10, the answer would be 0.4 by putting the decimal in front of the number.
